Folding leg assembly for airplanes and other usage



V. T. ABEL July 11, 1961 FOLDING LEG ASSEMBLY FOR AIRPLANES AND OTHER USAGE Filed Jan. 9, 1958 2 Sheets-Sheet 1 FIG. 2

INVENTOR VERNON T. ABEL ATTORNEY July 11, 1961 v. T. ABEL 2,991,830

FOLDING LEG ASSEMBLY FOR AIRPLANES AND OTHER USAGE: Filed Jan. 9, 1958 I FIG. 6 v

2 Sheets -Sheet 2 FIG. 7 4

7 15 as n I 38 17 FIG. 5 l3 15; 26 LL? I 27 I INVENTOR l W as VERNON T. ABEL ATTORNEY United States Patent 2,991,830 FOLDING DEG ASSEMBLY FOR AIRPLANES AND OTHER USAGE Vernon T. Abel, Baltimore, Md., assignor to.C. R. Daniels, Inc., Daniels, Md., a corporation of New York Filed Jan. 9, 1958, Ser. No. 707,907 Claims. (Cl. 28714) This invention relates to a folding leg assembly for use on airplanes as for example for troop seats, and for other purposes.

Prior art troop seats had either a stationary leg, or, where a folding leg was used, it was of such character that it was not possible to be locked in position. In some cases, the structures were so heavy, bulky, and cumbersome as to defeat their use for many purposes, particularly on airplanes where the demand was incessant.

Among the objects of the present invention are folding leg assemblies of light weight and simple but strong and rigid structure that may be locked in position for use either vertically as a support or horizontally when being stored for future use.

Other objects include such leg assemblies that may be utilized to tighten and tension seat bottoms, as for example, nylon seats, and locked in position to retain such tension.

Further objects include multiple leg and seat structures utilizing a multiplicity of folding leg assemblies in locked juxtaposition to get seats of any desired width.

Other and further objects and advantages will appear from the more detailed description set forth below, it being understood that such more detailed description is given by way of explanation and illustration, but not as limiting, since various changes may be made therein by those skilled in the art without departing from the spirit and scope of the present invention.

In connection with such more detailed description, the

drawings show the following.

FIGURE 1 is front elevation of one form of leg assembly in accordance with the present invention.

FIGURE 2 is a section on line 2-2 of FIGURE 1.

FIGURE 3 is a fragmentary detailed elevational view of the leg assembly of FIGURE 2.

FIGURE 4 is a section on line 2-2 of FIGURE 1 showing a modified form of locking element.

FIGURE 5 is a section on line 2-2 of FIGURE 1 showing a further modified form of locking element. [FIGURE 6 is a fragmentary top plan view of a pair of juxtaposed leg assemblies.

FIGURE 7 is a section on line 7--7 of FIGURE 6.

In accordance with the present invention, a folding leg assembly is provided particularly useful for support of troop seats on airplanes but useful for other purposes as Well. Such leg assembly provides a simple and economical seat support that is safe, rigid and strong, which leg support may be shifted into either of two positions, the first being angular with respect to the seat or beam member for the seat, to support the seat for normal use, the second position being one where the leg is folded against the seat or beam in parallel, contiguous position for non-use and storage; the leg being releasablylocked in either position to prevent possible displacement. Further, since such seats are usually made of flexible seat material, such as nylon, the leg assembly of the present invention provides additionally for tensioning such nylon or other textile seat member to give it desired support characteristics, and also to enable such tension to be maintained even when the leg is collapsed to n0nsupp0rting position. Furthermore, the invention includes means for utilizing a number of such leg assemblies in associated material and locking means are provided to retain the tension thus supplied, by a tension-preserving locking pin. To produce a multiple seat assembly, the beams in each leg assembly are desirably tubular and may be releasably locked together in end-to-end juxtaposition.

Reference may be made to the drawings to illustrate these structures and functions.

Referring to FIGURES 1 to 3 of the drawings, leg member 1 supports metal ring section 2 which is attached to leg member 1 through channel section 3, ring section '2 encompassing beam 4. As illustrated, ring member 2 has circular ring strap 5 to which depending strap members 6 are brazed or otherwise secured, to form leg bracket 7, in which bolt 8 is supported forming an axis on which leg member 1 is mounted to permit relative rotary movement of leg member 1 with respect to beam 4 so that leg member may be moved into a vertical position as shown in FIGURES 1 to 3 to support beam 4 or as shown in dotted lines in FIGURE 1 may be moved into non-supporting position 9 for non-use or storage substantially parallel with and contiguous to beam 4. Ring strap 5 has longitudinal slot or opening 10 to expose a substantial portion of beam 4 for purposes hereinafter set forth.

In order to lock leg member 1 against relative movement to and from beam 4, leg locking pin 11 is mounted on leg member 1 to enter any of the series. of circumferentially spaced 'holes 12 in beam 4. The stmc-i ture for this purpose is shown in FIGURES lto 3. Leg member 1 carries tubular plug 13 positioned in upper end 14 of leg member 1, leg locking pin 11 reciprocating in channel 15 of tubular plug 13, locking pin 11 terminating in stud 16, said pin 11 being urged outwardly by coil spring 17 placed in channel 15, one end of the wardly through slot 26 to knob 27 mounted on said It will be apparent that by pulling down on knob' shaft. 27, the latter may move downwardly in slot 26, whereby leg locking pin 11 is compressed against spring 17 to move stud 16 away from beam 4. Release of knob 27 permits restoration of locking pin 11 to normal position. Locking pin 11, pilot shaft 20 and guide base 24 act as a unit and may be made in any desired way. For

example, if made as three separate pieces they may be assembled for use, or these elements may be made into a combination of two pieces and then assembled.

When leg member 1 is in horizontal position 9 as shown in dotted lines in FIGURE 1, stud 16 extends through lateral hole 28 in channel section 3 whereupon stud 16 locks leg member 1 in such horizontal position. To erect the leg into vertical position, stud 16 is disengaged by depressing knob 27 to retract leg locking pin 11, and leg member 1 moved arcuately downward With knob'27 still depressed, beam 4 is rotated axially until proper tension is attained on the nylon seat attached to beam 4. Such seat and attachment is Well known and Patented July 11, 1961 is not illustrated. (See Evans Patent No. 2,556,077.) When proper tension has been obtained, a circumferential hole 12 in beam 4 is lined up with lateral hole 12' in metal ring section 2, and knob 27 released, whereupon stud 16 enters the bottommost circumferential hole 12 in beam 4 to lock leg member 1 in supporting position while retaining the predetermined tension on the nylon seat. Circumferentially spaced holes 12 in the periphery of beam 4 are supplied so that a hole 12 will be aligned with stud 16 in any position where beam 4 has been placed. In such structure, the various parts are releasably locked in position. The leg assembly is of simple construction, economically manufactured and foolproof in operation and is well suited for use as a folding type leg in troop seats for aircraft.

If it is desired to lock the tension on the seat bot:- tom so that the tension will not change when the leg is in folded or non-supporting position, this may be accomplished in any desired way, several such expedients being illustrated below.

One of the simplest arrangements for this purpose is shown in FIGURE 4 the locking mechanism being placed toward the rear. Being in the back, it prevents snagging of cloth, clothing, etc. In this arrangement, lateral opening 29 in metal ring section 2 is aligned with a circumferential hole 12 in beam 4. Boss 30 is brazed or otherwise attached securely to metal ring 2 over opening 29 extending outwardly in a radial position. Boss 30 has an internally threaded passage 31 in which wing screw 32 is seated. The inner end of the screw is pin-shaped at 33 to enter alined openings 12 and 29 to lock beam 4 against rotation in metal ring section 2 thereby retaining the pre-set tension in the seat member regardless of any movement of leg memher 1. The screw may be retracted to release the beam.

An alternative structure is shown in FIGURE 5. Here with holes 12 and 29 alined, they are lined up with tubular boss 34 brazed or otherwise secured on metal ring member 2. Shaft 35 is attached at the outer end to knob 36 and at its inner end to locking pin 37, while coil spring 38 seats on one end on the wall of boss 34 and at the other against pin 37. Normally spring 38 urges pin 37 into locking position, but retraction of knob 36 releases beam 4 for axial movement.

A third arrangement is that shown in FIGURES 2 and 3. Here leaf spring 39 has one end 40 positioned on bolt 8, the other end 41 having hole 42 which receives locking pin 43 having knob 44 on its outer end, pin 43 entering alined holes 12 and 29. Flat spring 39 has hole 42 in the upper end. Locking pin 43 and knob 44 are two separate and individual pieces with a hole through. A rivet is placed through the hole in locking pin 43 through the flat spring 39 and then through the knob 44 and is riveted into contact. Retainer and guide 45 is a small bracket that is welded or brazed or fastened on to channel 3 and acts as a determining factor to control the extent that the flat spring may be pulled out and acts as a guide for the flat spring which eliminates the possibility of the locking pin 43 from being dislocated. Spring 39 moves freely Within guide 45. By retraction of knob 44, locking pin 43 is disengaged to permit beam 4 to rotate, and upon release of knob 44, the parts return to normal locking position. Retainer and guide 45 prevents excessive bending and dislocation of the spring. Otherwise the second and third arrangements discussed above serve to obtain a locking and releasing function as described for the first arrangement. Arrangements 2 and 3 are simple in structure, are light in weight, foolproof in operation and economical to manufacture.

Along with the manufacture of a variable width troop seat, it is desirable to produce a structure that enables two or more leg and seat assemblies to be releasably interlocked with their beams in end-to-end juxtaposition; and also to provide a structure whereby such interlocking mechanism may be stowed in locked position when the beams are not joined together. FIGURES 6 and 7 of the drawings illustrate such structures. Beams 4 and 4' represent front tubular beams of two leg and seat assemblies in releasably interlocked end-to-end juxtaposition. Within beam 4, sleeve 45 is fastened. In airplane use, such sleeve is cut down wherever possible and contacts beam 4 where necessary for attachment, in order to eliminate as much weight as possible.

Within beam 4' two retaining rings 46 and 47 are attached internally to said beam 4' in spaced apart relation to form a locking element. Ring 46 is mounted adjacent to end of beam 4' and is provided with ridge 48 to enter and close any space between the juxtaposed ends of beams 4 and 4'. This raised ridge eliminates the possibility of an occupant having a thigh pinched between the ends or edges of beams 4 and 4'.

Beam 4 carries internally a bolt type locking element 49 including a sleeve 50 adapted to slide internally of beam 4 to bridge the juxtaposed ends of beams 4 and 4'. A locking element is mounted on said sleeve 50 to cooperate with the retaining rings 46 and 47 to releasably lock the bolt and beams together. Such locking element may include leaf spring 51 attached internally of bolt sleeve 50 at end 52 thereof with spacer 53 between spring 51 and sleeve 50. Stud 54 is carried on spring 51 and is adapted to enter the space between retaining rings 46 and 47 to lock the beams together. At outer end 55 of spring 51, shaft 56 is mounted and extends through cutout 57 in sleeve 50 and slot 58 in beam 4, externally thereof where actuator button 59 is attached to said shaft. It is desirable for bolt 49 to slide freely and easily in sleeve 50 and within rings 46 and 47. The distance of travel of bolt 49 is governed by the length of slot 58.

To unlock or disengage beams 4 and 4, actuator button 59 is depressed whereby stud 54 is disengaged from retaining rings 46 and 47. Bolt 49 may then be retracted into beam 4 until end 52 of sleeve 50 and the end of beam 4 are flush. Notch 60 is cut in sleeve 50 so that when bolt 49 is fully retracted, and actuator button 59 is released, stud 54 enters notch 60 to lock the bolt in stored position.

To join or lock beams 4 and 4' together, the ends of the beams are juxtaposed and actuator button 59 depressed to disengage stud 54 from notch 60. The bolt is then moved into beam 4' the entire distance permitted by slot 58 until stud 54 snaps into position Within the space between retaining rings 46 and 47. Actually ring 47 may be omitted if desired since slot 58 will limit movement of the bolt; but its presence gives a more rigid structure. As noted, spring 51 is fastened at the far end of the bolt from that of button 59, with stud 54 located in between. Consequently any force tending to pull the locked beams apart, actually locks them together more firmly since the applied force is pulling upwardly against the spring rather than depressing it. By making each beam to have one female and one male end, it is possible to combine and lock all the seats of a row into one continuous seat or bench making a variable width troop seat.

Having thus set forth my invention, I claim:

1. A locking folding leg assembly for seats and the l ke including a leg member, a metal ring member section including spaced strap portions mounted on said leg member, a beam carried within said ring member for axial rotation with respect thereto, said beam being provided with circumferentially spaced apertures, a channel member on said ring member section, said channel member being provided with a laterally disposed aperture, the leg member being pivotally mounted on said channel member to move into one of two positions, one being an angular position with respect to the beam to support the latter and the other being in a folded position parallel and contiguous to said beam for non-supporting and storage position, a locking member carried by said ring member section and selectively engageable with one of said plurality of circumferentially spaced apertures in the beam to lock said beam in axial adjustment, said apertures being located intermediate the spaced strap portions of the ring member section for ready visibility, and a retractable locking element within the leg member selectively cooperating with one of the apertures in the beam to lock said leg member in supporting position or with the aperture in the channel member to lock said leg in storage position.

2. The leg assembly as set forth in claim 1 in which the locking element on the leg includes a spring-pressed locking pin.

3. The leg assembly as set forth in claim 2 in which the leg member is provided with a slot, a shaft attached at one end to the locking pin and extending through the slot in the leg member externally of the leg member for reciprocating the locking pin toward and away from the beam.

4. The leg assembly as set forth in claim 3 in which the ring section is provided with a basehole located at the bottom of the ring section through which the locking pin passes to cooperate with the apertures in the beam.

5. The leg assembly as set forth in claim 4 in which the ring section is also provided with a pilot hole in the side thereof to align with one of said circumferentially spaced holes in the beam thereby to align one of the other circumferentially spaced holes in the beam with the base hole for reception of the locking pin.

6. The leg assembly as set forth in claim 5 in which the metal ring section is provided with an additional lateral opening adapted to align with a circumferential hole in the beam, and in which said locking member carried by said ring member includes a tubular boss on the ring section with a central passage in the boss aligned with said lateral opening, and a tension-preserving locking pin movable in said passage to lock the beam in position when the leg is in folded position.

7. The leg assembly as set forth in claim 6 in which the passage and tension locking pin are threaded for interengagement.

8. The leg assembly as set forth in claim 6 in which the tension-preserving locking pin is spring-pressed inwardly to urge the last mentioned pin into locking position, and a knob on the outer end of the last mentioned pin for manually moving said pin into release position.

9. The leg assembly as set forth in claim 1 in which the locking element on the leg includes a spring-pressed locking pin and the ring section is provided with a pilot hole in the side thereof to align with one of the circumferentially spaced apertures in the beam thereby to align one of the other circumferentially spaced holes in the beam for reception of the locking pin.

10. The leg assembly as set forth in claim 9 in which the metal ring section is provided with a lateral opening adapted to align with a circumferential aperture in the beam, and in which said locking member carried by said ring member includes a tubular boss on the ring section with a central passage in the boss aligned with said lateral opening, and a tension-preserving locking pin movable in said passage to lock the beam in position when the leg is in folded position.

References Cited in the file of this patent UNITED STATES PATENTS 450,737 Deimel Apr. 21, 1891 942,085 Linder Dec. 7, 1909 975,996 Reed Nov. 15, 1910 1,135,707 Mattes Apr. 13, 1915 1,578,598 Gidney Mar. 30, 1926 1,620,404 Sprague Mar. 8, 1927 1,811,936 Hutchins June 30, 1931 1,844,410 Schalk Feb. 9, 1932 1,879,036 Bell Sept. 27, 1932 1,934,396 Bales Nov. 7, 1933 2,135,263 Sisson Nov. 1, 1938 2,473,388 Rambo June 14, 1949 2,544,977 Blank Mar. 13, 1951 2,556,077 Evans et al June 5, 1951 2,577,817 Schueder et a1. Dec. 11, 1951 2,586,262 Robins Feb. 19, 1952 2,599,164 Cudini June 3, 1952 2,614,781 Engel Oct. 21, 1952 2,692,153 Schlueter Oct. 19, 1954 2,709,481 Budai May 31, 1955 FOREIGN PATENTS 4,085 Great Britain Mar. 2, 1892 562,652 Germany Oct. 27, 1932 420,733 Great Britain Dec. 6, 1934 

